Bug 638579
| Summary: | dasd: fix race between tasklet and dasd_sleep_on [rhel-5.5.z] | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 5 | Reporter: | RHEL Program Management <pm-rhel> |
| Component: | kernel | Assignee: | Jiri Pirko <jpirko> |
| Status: | CLOSED ERRATA | QA Contact: | Red Hat Kernel QE team <kernel-qe> |
| Severity: | high | Docs Contact: | |
| Priority: | high | ||
| Version: | 5.5 | CC: | brueckner, cww, dhoward, eguan, gbarros, jkachuck, jpirko, pm-eus, rkhan, tao, yugzhang |
| Target Milestone: | rc | Keywords: | ZStream |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: |
Various dasd_sleep_on functions use a global wait queue when waiting for a CQR (Channel Queue Request). Previously, the wait condition checked the status and devlist fields of the CQR to determine if it is safe to continue. This evaluation may have returned true, although the tasklet did not finish processing the CQR and the callback function had not been called yet. When the callback was finally called, the data in the CQR could have already been invalid. With this update, the sleep_on wait condition has a safe way to determine if the tasklet has finished processing, thus, preventing the aforementioned behavior.
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Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | 2010-11-09 18:09:23 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | 593756 | ||
| Bug Blocks: | |||
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Description
RHEL Program Management
2010-09-29 12:21:29 UTC
in kernel 2.6.18-194.18.1.el5 linux-2.6-s390-dasd-fix-race-between-tasklet-and-dasd_sleep_on.patch An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2010-0839.html
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New Contents:
Various dasd_sleep_on functions use a global wait queue when waiting for a CQR (Channel Queue Request). Previously, the wait condition checked the status and devlist fields of the CQR to determine if it is safe to continue. This evaluation may have returned true, although the tasklet did not finish processing the CQR and the callback function had not been called yet. When the callback was finally called, the data in the CQR could have already been invalid. With this update, the sleep_on wait condition has a safe way to determine if the tasklet has finished processing, thus, preventing the aforementioned behavior.
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